SUMMARY1. Reliable assessments of groundwater biodiversity are urgently needed to resolve current issues relating to the protection of aquifers. The assessment of groundwater biodiversity is hampered by the physical complexity and difficult access to the subterranean environment, which is related to the vastness, high degree of fragmentation and environmental heterogeneity of groundwater systems. Knowledge on groundwater biodiversity is also biased towards penetrable karstic habitats (caves), whereas other common habitats such as those found in porous aquifers have been neglected. This situation calls for a standardised and comprehensive strategy to sample an exhaustive and balanced set of groundwater habitats. 2. A standardised sampling protocol aimed at capturing the main sources of environmental heterogeneity within regions was applied in six regions across Europe. Four hierarchical levels were considered: (i) region (c. 400 km 2 ); (ii) basin (c. 100 km 2 ); (iii) aquifer type (karstic or porous) and (iv) habitat (hyporheic and phreatic zones for porous aquifers; saturated and unsaturated zones for karst aquifers). A total of 192 sampling sites equally distributed among habitats were sampled within each region. 3. Stygobiotic species richness significantly varied across regions, probably as a result of important difference in physical and biogeographical characteristics among the regions. Only one species (Graeteriella unisetigera) occurred in all six regions, underlining the narrow geographic range and high degree of endemism of stygobiotic fauna. The low frequency of occurrence of stygobionts also points to the importance of rarity in ground waters and its relevance for drawing up sampling designs. 4. Rarefaction curves were calculated to determine sampling efficiencies within each region. Despite the high sampling effort, the curves did not reach saturation, especially in the Cantabria, Lessinia and Krim regions, which had the greatest numbers of rare species. 5. Species accumulation curves were also calculated by considering the main sources of environmental heterogeneity among basins, aquifer types and habitats captured by the sampling protocol. In two regions (Roussillon and Jura) sampling efficiency was improved
Ground waters have exceptional conservation value due to the high endemism of their biota, the high occurrence of species relicts and because they are the second most important reservoir of freshwater after the glaciers. We used habitat-based models to predict the distribution of obligate groundwater species (stygobionts) in the Jura Mountains, eastern France. Current and historical environmental variables were selected to predict the occurrence of 19 stygobionts collected in different groundwater habitats. Species occurrence was weakly correlated with most of the physico-chemical variables and better correlated to habitat type, elevation gradient, hydraulic conductivity and the distance of the last glacial event. We identified two main groups of species, those whose distributions correlated with the last glacial event and those that did not. Our findings suggested that abilities for migrate and opportunities for dispersal using connections among habitats may explain part of these distributions and that specific spatial components should be incorporated in future modelling. We propose the identification of rich-species areas and protection of the complete spectrum of GW habitats as pertinent measures to achieve the stygobitoic persistence.
Introducción 6 El patrimonio biocultural y la problemática socioambiental 8 Una alternativa a la problemática ambiental, social y económica 10 Antecedentes de esta visión alternativa 10 Sobre este documento Capítulo 1: Marco Conceptual Ecosistemas, servicios y beneficios a la sociedad Sociedad e impactos sobre los ecosistemas: fomentando unos beneficios a costa de otros El deterioro de los sistemas socio-ecológicos El desarrollo sustentable Capítulo 2: Integrando la Visión Ecosistémica en el Ciclo de las Políticas Públicas 24 Estudio de Caso en México: El Desarrollo del Sector Primario en el Norte y Noroeste La visión ecosistémica en el ciclo de las políticas públicas Iniciación Recuadro 1: Contexto, antecedentes y objetivo de las políticas de desarrollo Recuadro 2: Ecosistemas y servicios ecosistémicos que sostienen al sector primario Previsión Recuadro 3: Deterioro ecológico y sus consecuencias Recuadro 4: Algunas tendencias y escenarios futuros Selección Recuadro 5: Las opciones de políticas Implementación Evaluación Capítulo 3: Propuesta para una Nueva Gestión para la Sustentabilidad 66 Toma de decisiones y políticas convencionales: un diagnóstico Cambios necesarios para la gestión sustentable de sistemas socio-ecológicos De gobierno a gobernanza De administración a co-manejo adaptativo Conclusiones:
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